a) Cut/copy and paste allows you to select a section of text and insert a new copy of that text. You can also transfer data from one place to another.
b) Save is when you keep your work for later and it will be the same as you left it. Think of it like putting a bookmark in your book. Save as lets you name the files.
c) Close and Exit just let you leave the program, saying you are finished working with it and want to do something else.
 
        
             
        
        
        
Explanation:
10:A program that assigns the sum 20,30,40
20: input 20,30,40
30:sum input
40: print total
End
 
        
             
        
        
        
Answer:
Aqueous carbon dioxide, CO2 (aq), reacts with water forming carbonic acid, H2CO3 (aq). Carbonic acid may loose protons to form bicarbonate, HCO3- , and carbonate, CO32-. In this case the proton is liberated to the water, decreasing pH. The complex chemical equilibria are described using two acid equilibrium equations.
PLS MARK AS BRAINLIEST
 
        
             
        
        
        
Viable and true. hope this helps!